MCM2 and ocular melanoma: Consistent with this ordering, preventing Cdt1 release with a Mcm2-7 ATPase mutant extends the duration of OM interactions (average OM duration after first Mcm2-7 arrival is 30 ± 2 s for wild type and 156 ± 14 s for the Mcm2-75RA mutant) and prevents formation of MO interactions.